As in the case of all other tires, there is a trend towards the use of radial motorcycle tires, the architecture of such tires comprising a carcass reinforcement formed of one or two layers of reinforcing elements making an angle with the circumferential direction which can be between 65° and 90°. Said carcass reinforcement is surmounted radially by a crown reinforcement formed of reinforcing elements. The invention also relates to partially radial tires—that is, tires in which the reinforcing elements of the carcass reinforcement are radial in at least part of said carcass reinforcement, for example in the part corresponding to the crown of the tire.
Many architectures have been proposed for the crown reinforcement, depending on whether the tire is to be mounted at the front of the motorbike or at the rear. A first structure for said crown reinforcement involves using only circumferential cables, and said structure is more particularly used for the rear position. A second structure, directly inspired by the structures often used on tires for passenger vehicles, has been used to improve wear resistance, and involves using at least two working crown layers of reinforcing elements which are approximately parallel to each other within each layer but intersect from one layer to the next, forming acute angles with the circumferential direction, such tires being especially suitable for the front of a motorbike. Said two working crown layers may be accompanied by at least one layer of circumferential elements, usually obtained by helically winding a band of at least one rubber-coated reinforcing element.
Which architecture is selected for the tire crown directly affects certain properties of the tire such as wear, endurance, grip, or ride comfort or, in the case of motorcycles in particular, stability. However, other tire parameters such as the type of rubber compounds forming the tread, also affect the properties of said tire. The selection and type of rubber compounds forming the tread are, for example, essential wear property-related parameters. The selection and type of rubber compounds forming the tread also affect the tire's grip properties.